Though dead humans can't come back to life, certain viruses can induce such aggressive, zombie-like behavior, scientists say in the new National Geographic Channel documentary The Truth Behind Zombies, premiering Saturday at 10 p.m. ET/PT. (National Geographic News is part of the National Geographic Society, which part-owns the National Geographic Channel.)

For instance, rabies—a viral disease that infects the central nervous system—can drive people to be violently mad, according to Samita Andreansky, a virologist at the University of Miami's Miller School of Medicine in Florida who also appears in the documentary.

Combine rabies with the ability of a flu virus to spread quickly through the air, and you might have the makings of a zombie apocalypse.

Rabies Virus Mutation Possible?

Unlike movie zombies, which become reanimated almost immediately after infection, the first signs a human has rabies—such as anxiety, confusion, hallucinations, and paralysis—don't typically appear for ten days to a year, as the virus incubates inside the body.

Quoting: Storm*

that's messed up, man..thanks for posting

Quoting: aBiNoRmAl

You're welcome. Pretty scary stuff. They say any attempt to engineer such a virus would probably result in a dead virus. But just the fact they put it out there makes you wonder.